1. Technical Field
The present invention relates in general to cordless power tools. In particular, the present invention relates to a battery release arrangement for a cordless power tool.
2. Discussion
Cordless power tools are used in a wide variety of applications. For example, various cordless vegetation trimming devices are used to trim vegetation such as grass or weeds in areas such as along walls of buildings, fences, around shrubs, and other areas where lawn mowers and other like apparatuses are not able to easily access. Other cordless vegetation trimming devices are used to manicure shrubs, trees and the like. In addition to vegetation trimming devices, cordless power tools include drills, impact wrenches, and the like.
The benefits of battery powered devices over conventional AC powered and gasoline powered devices have long been recognized. For example, batteries generally provide a cleaner and less costly form of power compared to gasoline or other combustible fuels. Also, battery powered engines generally have increased reliability and lower maintenance compared with gasoline engines. Compared with AC powered devices, battery powered devices are not fraught with the disadvantages associated with a power cord, including but not limited to the restricted distance the device can be operated from an electrical outlet. Historically, battery powered devices have been associated with limited operational life between recharging and lower performance. However, modern battery technology has greatly improved battery life and performance, resulting in a corresponding increase in consumer popularity with cordless power tools.
It has been found convenient to have the battery packs of cordless power tools releasably mounted within the housing so that the battery packs can be removed quickly and easily for recharging. During this recharging, the battery packs are placed in a charging unit connected to a source of AC supply. While the battery packs are in place in the cordless power tools, it may be desired to securely latch them in position.
It is known to facilitate the removal of rechargeable battery packs through the incorporation of a release arrangement. Most known battery release mechanisms utilize an independently manufactured biasing spring which operates to normally urge the mechanism to a latched condition. One known release mechanism is shown in U.S. Pat. No. 4,871,629 to Bunyea. This patent is assigned to the assignee of record of the present invention and is expressly incorporated herein by reference.
The battery release mechanism for a cordless power tool disclosed in U.S. Pat. No. 4,871,629 is specifically adapted to cooperate with a battery pack having a casing with a shoulder on its outside surface. The release mechanism includes a spring member having a displaceable limb resiliently biased against the casing. A manually actuatable latch release member is movably mounted in the power tool between a latching position and a release position. The limb normally blocks the shoulder in the latching position to latch the battery pack in the power tool. The release member functions to displace the limb away from the casing and clear of the shoulder in the release position to unlatch the battery pack and allow withdrawal thereof from the power tool. In the embodiment described, the release member comprises a yoke straddling the battery pack.
While prior known devices such as the one discussed above have generally proven to be commercially successful, it is further desirable, however, to provide a battery pack release arrangement for a cordless power tool that does not require a separately manufactured spring member for urging the release arrangement to a latched position.
In view of the above, it is a principal object of the present invention to provide a release arrangement for the battery packs of a cordless power tool having a simple yet effective construction normal in a latched condition which does not require a separately manufactured spring member.
It is a further object of the present invention to provide a release arrangement for the battery packs of a cordless power tool that has a minimum number of components and is easily operated with a single hand.
It is another object of the present invention to provide a battery pack release arrangement having components that are less subject to wear, thereby resulting in a power tool having reliability over a longer period of time.